Rinsing system for dishwashing machines



Jan. 16, 1966 C. R. WEIHE, JR# 3,363,636

RINSING SYSTEM FOR DISHWASHING MACHINES r Filed Jan. 19, 1966 u nl u m nl United States Patent O 3,363,636 RINSING SYSTEM FOR DISHWASHING MACHINES Clyde R. Weihe, Jr., Needham, Mass., assignor to Adamation Inc., Newton, Mass., a corporation of Massachusetts Filed Jan. 19, 1966, Ser. No. 521,594 2 Claims. (CI. 134-72) ABSTRACT OF THE DISCLOSURE A rinsing system for commercial dishwashing machines, designed to rinse the dishes first in clear and then in water containing a drying agent. The rinse water inlet pipe is connected to two branch pipes leading to two spray pipes at separate stations. A supply for drying agent is connected to one of the branch pipes. The dishes are passed first through the clear water spray and then through the spray containing drying agent.

This invention relates to dishwashing machines and more particularly to rinsing systems for machines of the commercial type.

Most state laws require that dishes for use in public places, such as restaurants, be rinsed with a certain quantity of fresh water in the final rinse stage. It is also customary to introduce a drying agent into the final rinse water to insure that the dishes dry quickly. The object of this invention is to provide a rinse system which satisfies the requirements for the quantity of rinse water used, and effects a substantial saving in the amount of drying agent which is needed in the final rinse.

According to this invention the drying agent is introduced during the last portion only of the final rinse cycle. In one embodiment, suitable for the continuous type of dishwashing machine, the final rinse is divided into two stations. At the rst station the dishes are rinsed with plain fresh water, and at the second station the dishes are rinsed with fresh water to which the drying agent has been added. In another embodiment suitable for the door type of dishwasher, which is cycled in the customary manner by a timer, an injector for drying agent is installed on the machine and operated by a valve controlled by the timer. The valve is opened only for the latter part of the rinsing cycle. Other objects, advantages, and novel features of the invention will be apparent from the following description.

In the drawings illustrating the invention:

FIG. l is a side elevation, with the housing partly broken away, of a continuous dishwashing machine with a rinse system constructed according to the invention; and

FIG. 2 is a side elevation of a door type of machine with the rinsing system installed.

FIG. l illustrates a continuous dishwashing machine having a cabinet 10. A conveyor track 11 passes through the cabinet, and it is understood that dishes disposed in racks may be moved along the conveyor in any suitable manner. The cabinet has open ends covered by ilexible curtains 12 and 14, and is divided by a flexible curtain 14 into a wash compartment 15 and a rinse compartment 16. It is also understood that the cabinet may include additional compartments, such as a prewash compartment. Spray pipes 17, in the washing compartment 15, are

Patented Jan. 16, 1968 supplied with wash Water including a detergent in the usual manner. A catch tank 1S is disposed below the cabinet. A pair of spray pipes 19 is disposed in the rinsing compartment 16. The pipes are supplied with fresh rinse water at the proper temperature through a main supply pipe 20, connected to a water supply (not shown) and leading to the pipes 19 through a branch 21. A second branch pipe 22 leads from pipe 20 to a pair of spray pipes 23 mounted in a third compartment 24. This compartment has open ends covered by flexible curtains 25 and 26. A rinse injector 27 is mounted on branch 22 to furnish the drying agent for the second station of the iinal rinse.

The operation of the device is as follows:

Dishes are carried along the conveyor track 11 in the direction of arrows 32. The dishes pass first through the wash compartment 15 and then to the rinse compartment 16, which constitutes the first station of the final rinse, and iinally to compartment 24, which constitutes the second station of the final rinse. The rinse water entering pipe 20 is divided at the T connection 29, so that part flows through pipe 21 in the direction indicated by arrow 28, and part liows through pipe 22 in the direction indicated by arrow 30. By suitably adjusting the relative sizes of pipes 20 and 22 and the spray outlets, any desired proportion of water may be distributed between the spray pipes 19 and the spray pipes 23. Preferably about one-third of the water is directed to pipeS 23 in the second station and about two-thirds to pipes 19 in the rst station. For example, if the total water requirement for the final rinse is six gallons per minute, four gallons per minute is directed to pipes 19 and two gallons per minute to pipes 23. The drying agent from the injector 27 is directed only to pipes 23, therefore only a third of the amount of drying agent is required, to produce the same concentration and the same drying action, in the last rinsing operation, as compared to the usual system in which the agent is added to the total volume of final rinse water.

FIG. 2 illustrates a typical door type of machine having a housing 35 and a door 36 through which racks of dishes are inserted and removed. The machine contains spray pipes 37 which are connected to a water supply line 38 controlled by a valve 39. The machine is run through various washing and rinsing cycles in the usual manner by a timer 40 which controls the opening and closing of valve 39. As is customary, the last stage of the cycle is the nal rinse. A drying agent injector 41 is connected through a valve 42 to pipe 38, valve 42 is also controlled by the timer 40. The timer is set so that valve 42 opens during only the last portion of the final rinse stage. For example, if the time cycle for the final rinse is 12 seconds, valve 42 opens during only the last three to four seconds. The dishes are thus rinsed with clear water for the first part of the final rinse cycle, and with the water to which the drying agent has been added to produce the usual concentration during the last part of the cycle. This arrangement produces the same drying effect, while using only about a third of the amount of drying agent, as compared to the usual systems in which drying agent is injected during the entire final rinse cycle.

The divided final rinse, in the first embodiment, and the extra timer Contact, in the second embodiment can be added, at very little expense, to new machines or to eXisting machines. In both cases there is a substantial saving in the cost of operation because of the smaller amount of drying agent required.

3 4 What is claimed is: substantially two-thirds of the water supplied by said inlet 1. A dishwashing machine comprising a nal rinse pipe passes said first spray pipe. stage including first and second rinsing stations, a first spray pipe mounted at said rst station, a second spray References Cited pipe mounted at said second station, a rinse Water 5 UNITED STATES PATENTS inlet pipe, a rst branch pipe connecting said inlet pipe to said rst spray pipe, a second branch pipe connecting f637 3/1953 Deum? *7 134"72 XR said inlet pipe to said second spray pipe, means for supply- 3767g lectenghl et al' ing drying agent connected to said second branch pipe, 3:320j964 5/1967 Troip; 134-100 and means for passing the dishes to said rst station and 10 then to said second station.

2. A dishwashing machine as described in claim 1, said CHARLES A' WILLMUTH Prlma'y Exammer' branch pipes and spray pipes being so proportioned that R. L. BLEUTGE, Assz'slant Examiner. 

